The Case for Heated Runways

Researchers Seek Ways to Warm Snowy Airport Surfaces

This winter over 76,000 flights have been cancelled, and it's only February. There may be a solution: heated airport runways can help cut down on flight interruptions. Middle Seat columnist Scott McCartney has the details on Lunch Break. Photo: AP.

The snow has been falling all day, but the plane takes off right on time, no delays, no hassles. The missing piece of the puzzle to make this dream of easy wintertime travel a reality: heated runways.

Research is under way around the world to find economical ways to heat airport surfaces or develop pavement resistant to freezing. Widespread use is still probably five or 10 years away, even though heated pavement is already used by hospitals, office buildings, shopping malls and luxury homes.

The desire for heated runways to keep planes moving in storms has taken on new urgency after this winter's serial snowstorms and nearly nonstop ice. The idea has been kicking around since the 1970s.

So far this year, more than 76,300 flights have been canceled, leaving millions of travelers in the lurch and costing airlines and airports millions in revenue. The number of flights canceled in January and February is double the number for the same period the past two years combined, according to FlightStats Inc.

Airports can't use salt because it is too corrosive to aluminum airplanes and jet engines, though there are some chemical deicing fluids that can be used on airport pavement. Plows and sweepers can clear runways and taxiways, but each time crews have to hit the runway, it slows operations considerably. Many airports have invested in tricked-out plows capable of clearing runways rapidly. Even those can't always keep up.

Some airports are using heated surfaces on a small scale. At Chicago's O'Hare International Airport, two taxiway bridges over roadways have embedded pipes that carry heated oil, keeping the surfaces free of snow and ice for planes without having to plow it onto passing cars below. At Oslo's Airport, some gate areas use geothermal heated-water systems to keep aircraft parking areas clear of snow and ice.

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Big airports like Boston's Logan International place giant snow-melters in terminal areas because snow can't just be pushed aside without blocking gates and roads. Often flights remain grounded even when weather has turned favorable for flying as storm cleanup can take a day or more. Of course, heated runways won't solve every winter storm issue. Airlines still face difficulties from lack of visibility for takeoffs and landings to ground workers unable to get to work.

The Federal Aviation Administration says heating systems could enhance safety, reduce snow removal time and minimize travel disruptions. But airports, airlines and the FAA all say it boils down to money: Heating large airport surfaces is too expensive.

"There's a better way to do this than snowplows going up and down. It's just a matter of finding it,'' said Ernie Heymsfield, an associate professor at University of Arkansas, who recently completed a solar-powered heated runway project for the FAA using concrete with steel fibers and graphite dust embedded in it to conduct energy. It wasn't reliable enough during cold and windy conditions, the team's report to the FAA said, and the costs were substantial.

ENLARGE

The Binghamton, N.Y., airport is a test site for a geothermal heating system.
McFarland Johnson, Inc.

Now Dr. Heymsfield is working on embedding wires in grooves in airport surfaces similar to wires embedded in a car's rear window.

The FAA is funding a large-scale test of geothermal heating at the State University of New York in Binghamton. Pipes have already been embedded in a gate area at the Binghamton airport terminal, and 20 500-foot-deep wells are currently being drilled. Testing could begin as early as March 1.

The wells are filled with tubes that carry water deep below the surface where it is heated to 55 degrees. Then the temperature is boosted with a heat pump, and the water is used to warm antifreeze that circulates under the airport tarmac. The hope is that it will be cheaper to operate over large surfaces than an all-electric system. If it works, "you never have to shut things down theoretically,'' said William Ziegler, the associate professor running the research.

The FAA says it just awarded two grants to Iowa State University, one to look at the economics of heated pavements at both large and small airports and the other to study concrete coatings that repel water. The FAA also gave Purdue University funding to study materials that could be added to pavement to delay freezing. But some in the aviation industry say airports should be taking the lead, rather than waiting for the FAA.

There are no firm estimates of what it would cost to heat runways. Most of the expense comes from operating the systems, not from installing them. So much energy is required that they've only been appropriate for limited pavement areas, said Chris Oswald, vice president of safety and regulatory affairs at Airports Council International, an industry group representing airports. "They really aren't feasible as replacements for conventional winter" snow removal, he said.

"Nobody looks at what it costs not to do it,'' said Alex Wilcox, an early executive of JetBlue Airways and now chief executive of a private jet firm. He got stuck with his 9-year-old daughter for 12 hours on Jan. 3 at New York's Kennedy International Airport when the departure time of his JetBlue flight kept getting pushed back, he said, because airport plows couldn't keep up. He began thinking then of the tens of millions of dollars that might be saved with heated runways. "To me, it's pretty simple math,'' said Mr. Wilcox, who suggests passengers would willingly pay $1 extra in airport facility charges to fund heated runways.

People who already have heated pavement chuckle at the struggle. Richard Silverstein, a Chappaqua, N.Y., doctor who specializes in headache treatment, has a $250,000 electric system that heats 7,000 square feet of driveway and walkway. Patients come to his home office and he was worried they could easily slip on ice.

Dr. Silverstein said his system costs about $800 to run for 24 hours—before recent electricity rate increases. He thinks train stations, airports and other public places should have it.

"It's like the snow didn't snow there,'' Dr. Silverstein said of his driveway.

Airplanes are a technology that are only a flurry of ground-to air-missiles away from being obsolete - from a practical viewpoint. Given the unbelievable proliferation of small but sophisticated hand held weapons (every group picture of terrorists seems to have some idiot with a ground to air missile) isn't there a fundamental issue with throwing huge amounts of money at airplanes? And with driverless auto's coming fast, that will wipe out flights of under say 400 miles in a few years. Why not look beyond today and think about tomorrow a bit?

The cheapest energy in the world could be used to clear runways of snow by co-locating a steam power plant next to the airport. Coal and natural gas turbine power plants produce steam which is expanded through condensing steam turbines down to a vacuum, then the steam at vacuum pressure is condensed back to liquid - the heat released condensing the steam at vacuum pressure is lost to the atmosphere. This fact limits power plants to a thermal efficiency of 55%. Most power for the US is produced in this manner.

There are some gas turbine turbines that are located next to systems that need heat - in these cases, the heat from the condensing of the steam is captured usefully. The thermal efficiency of this cycle, measured in captured power and heat, exceeds 80%.

Steam at vacuum conditions is condensed at 130 - 150 deg F. There is very little application for heat at this low temperature - but the heating of concrete surfaces could use this low grade heat.

In summary, locating a steam power plant next to a runway could provide nearly free heat for snow melting.

Where is Carl Bialek when you need him? I just ran the numbers. Based on Dr. Silverstein's cost of $800 to heat 7,000 SF for 24 hours, and an average 10,000' x 200' runway, that pencils out to $228,571 to heat ONE runway for a day. Atlanta Hartsfield is the busiest airport in the world, and handles roughly that number of passengers in a single day using FIVE runways, so the $1 per ticket crowd are dreaming in technicolor.

Interesting article about heated runways. Could work. Passengers would pay a lot more than a $1 per seat.I really liked the mention of Dr. Silverstein who heats his 7000 S.F. Home office. I bet his services are not covered by O'Bamacare. And of course the IRS will never question this home office expense.

You can have all this "gee wiz" stuff and two weather phenomena will close the airport down no flights will depart and the runways will be relative clear. Sleet/Freezing rain near the airport or on the route....

While everyone is waiting for the "cure" this is my cure. It's called the automobile. Use airlines only as the last resort. I began doing this about a decade ago. I usually get where I want to be when I want to be there. No more unscheduled nights in expensive hotels because the airlines cancel my flight hours after the so called "scheduled" departure.

Does it take more time? My most recently cancelled flight required that I stay overnight, and because all flights were filled, put me on a flight 24 hours after the originally scheduled one. I could have driven in less than 10 hours.

Sorry, "the friendly skies," "the new AA" and that greyhound bus of the skies called "Southwest Airlines." I'm done with all of you and I now operate in accordance with the rules so succinctly stated by a former CEO of Southwest Airlines: "It's simple, get the passengers where they want to go, on time, and with their luggage." The airlines can't deliver, but my car can. My track record is much, much better than that of the airlines. I'm using 10 years of real data, comparing my results to those of the airlines. Yes, I do still fly from time to time, most recently 6,000 miles round trip. However, comparing real results I have been far, far more reliable. And, my luggage arrives too!

Nice idea, but the cost of runway and taxiway maintenance will be significantly increased if these are installed. 800,000 pound aircraft landing and taking off eventually cause runway to deteriorate and thus need replacement. Having this systems underneath the pavement will probably mean a much shorter life cycle for the runways and taxiways. That $1 extra facility charge is going to need to be increased significantly, maybe to $11, to cover all the maintenance costs of this system.

Why not use wastewater from the terminal itself? Water with human and other biological waste stays well north of freezing because of the bacterial activity going on inside it. Pipe it under the runway and you've got a ready made heat source. All that would be needed is a system for piping the stuff close enough to the runway surface to be effective without compromising the structural integrity of the pipes. The wastewater would ultimately go wherever it already goes (the sewer), but it would go there via a 12,000 foot runway instead of right out the door. Granted, the cost to retrofit existing airports would likely be prohibitive, but for new facilities could be designed for such system without too much extra cost (relatively speaking).

How about stop using airports in extreme cold weather climates as major hubs. Chicago for example. When Chicago cancels flights it ripples throughout the system. Perhaps Memphis, 500 miles to the south but nowhere near the snow, ice, wind etc.

Clearing the runways is great, but what about deicing the planes? Last year I was on a flight from YYZ where they cleared the runways pretty quickly, but there was a five hour queue for the deicing stations,.

Solar power is unreliable, per "Ernie Heymsfield, an associate professor at University of Arkansas, who recently completed a solar-powered heated runway project"

OK, this sounds like one of those overtly absurd fluff projects the Govt is famous for.... Using solar power to melt snow during a grey, overcast, windy winter storm dropping lots of snow... Yeah, right. Precisely when solar power DOES NOT work. So, we're left with fossil fuel or nukes.

Lots of factors in dealing with winter flying conditions in temperate climates. I flew in winter conditions and never had a problem -- in Puerto Rico and Hawaii.

It's not just the snow that causes problems. Air temperature is a factor, as is wind speed and direction. At very low temperatures melting snow causes an ice problem when the stuff immediately refreezes; a strong wind drifts snow across freshly cleared creates what are called "pillow drifts" and presents a takeoff hazard; very low temperatures on some airports create what is called "ice fog" or "habitation fog". Just ask the Russians about that phenomenon -- or anyone flying out of Alaska. Don't know whether the technique is still used, but we used to scatter urea fertilizer on parking areas and taxiways because it clears ice efficiently -- if the air temperature is around freezing. But it causes its own problems by polluting the runoff, which flows into streams and creeks.

They already have small versions of those for fog clearing attempts. Lousy results. Your solution neglects the fact that the melted snow area will be covered again or the melted snow will freeze into a sheet of ice after the machine passes. In addition using jet fuel that way is a bad resource use choice, similar to making paper from trees compared a more appropriate way of making it from grasses. A continuous heating system would provide for a large increase in uninterrupted runway and taxiway operations. Your solution would still require landing and takeoff disruptions.

Keep in mind you wouldn't be turning the system on in most places all day, just when it's snowing enough to cause problems. You may not even want to turn it on if your work staff or paying customers can't make it to the airport, or the airport you're headed to is socked in because it doesn't have the system. Weigh the expected annual cost against lost revenue to the carriers and the airport authority.

Pump antifreeze-water mixture from 10-15' ft underground. Ground that deep is typically around 50F. Figure out the depth that you need so that you don't bring the underground temp below 35F before the end of winter and you are set. All you need is pumps. Run the system in the summer to recharge the ground heat.

When I lived in PA, and heated my house with wood, we used ashes (which are darker than snow, thus pick up solar energy as heat) on the driveway. Didn't help at night or during a grey day during a storm, but melted stuff as soon as the sun came out. There is no easy answer DURING a winter storm that may be dumping over an inch of snow per hour, at 0 degrees, at night. You have to heat a runway 30+ degrees (in the wind!) just to get to freezing, plus provide the 'heat of fusion' of water that must be supplied to melt it (produce the phase change from solid to liquid - which is a huge amount of energy!).

Bottom line? Don't fly when it's that bad. Unless you want to burn HUGE amounts of fossil fuel or build a midsize nuclear reactor to heat maybe a square mile of pavement thirty degrees in the wind. Cue Al Gore on energy conservation:

Nice analysis, Anthony. I fear you are correct about the pipes becoming stressed members. In theory, that's okay; after all, they are monocoques. However, I fear that heat/cold cycles combined with the stresses would weaken the joints.

Craig's initial point about the thickness is much closer to reality; one has to heat a volume of concrete. A walkway's concrete thickness is a few inches and supports several hundred pounds . JFK's taxiways have to support an a380 that weighs 1.3 million pounds and the runways have to accept that same landing plane (now weighing "only" 900,000 pounds) and descending at a rate of about 10 feet per second.

When 31L was widened a couple years ago, the contractor stripped off only the first 18 inches of concrete, so that means the pipes have to be buried below that. So, I believe the running cost (to say nothing about amortizing the construction costs or paying for maintenance and repair) would be closer to 8x of Zach's estimate of $0.5 billion or $4.0B. Then, there's also Craig's point of maintaining the structural integrity of the runways and taxiways: the pipes would be places where the rebar can't be and thus become stressed members themselves.

For perspective, in 2012, the PANY/NY's entire utility cost for the airports, bridges, PATH trains and buildings it operates was $174 million and ConEd's total revenue was $12.2 billion. Something tells me that finding another $4B of local power won't be easy or quick.

As a NYC resident, I don't place enough faith in this entity's management to administer a program of this scale regardless of its merit, just ask the residents of Ft. Lee.

Actually, it's likely worse. Runways are VERY thick, unlike driveways and sidewalks. I'm not sure if putting the pipes near the surface would weaken the strength of the concrete, but you could wind up having to heat a much thicker slab.

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